Question: Kevin did 20 fewer push-ups than Tiffany in the morning. Tiffany did 43 push-ups. How many push-ups did Kevin do?
Answer: Tiffany did 43 push-ups, and Kevin did 20 fewer than that, so find the difference. The difference is $43 - 20$ push-ups. She did $43 - 20 = 23$ push-ups.